With the expanding of the power system , power plants are far away from each other geographically , and the network loss caused by power transmission among power plants must be considered during economic dispatch and control 随着电力系统规模的扩大，各发电厂在电力系统中的地理位置相距较远，在进行经济分配时，则必须考虑电厂间输电线传送功率所带来的网络中的有功功率损耗。
Single phase ac active power meter : single screen digital display ; outline dimension 9648 mm ; no communication interface ; no transmission output ; no alarm output ; switch power supply ; input voltage 0400 v ; input current 05 a ; power display 02000 w 单相交流有功功率表:单屏数字显示;外形尺寸9648 ;无通讯接口;无变送输出;无报警输出;开关电源供电;输入电压0 400v ;输入电流0 5a ;功率显示0 2000w 。
Lastly , we have solved the problem of being not able to control coupling of active power and reactive power of bdfm independently by using the vector control and at the same time we provided a control equation with concise form and project easy to achieve 最后，利用矢量控制解决了无刷双馈电机有功功率和无功功率相互耦合不能独立控制的难题，并给出了形式简洁的控制方程和易于实现的控制方案。
Furthermore , sampling and processing of ac , including some ac sampling algorithms , are reached . mainly , fft algorithm and full - wave fourier algorithm are discussed . calculation of active power and imaginary power is researched 同时对模拟量的采集与处理以及一些交流采样的算法进行了研究；主要就快速傅里叶变换算法、全波傅氏算法以及有功功率、无功功率的计算、滤波的参数选取、谐波的计算进行了讨论。
This thesis studies a measuring system of three phrase electricity parameter based digital sampling method . its function includes the measuring of current , voltage , fre - quency , phrase , factor , active power and energy , reactive power and energy 本文主要研究基于数字采样测量方法中的同步采样法设计的三相电参数测量系统，主要功能包括电流、电压、频率、相位、功率因数、有功功率、电能、无功功率、电能等的测量。
In power system , it can effectively improve the voltage and decrease the real power loss that coordinated control the transformer tap and the compensatory capacitor of the region network . the voltage and reactive power control makes the running of the systems more safe and stable and economical 在电力系统中，对地区电网中的有载调压变压器和补偿电容器进行协调控制，能够有效提高电压水平、降低有功功率损耗，对系统的安全稳定经济运行具有重要意义。
Based on the large disturbance equation and using the measured power angle as an observation argument in an identification algorithm , the electrical parameters and mechanical parameters are obtained . in this thesis , micro - computer testing systems for synchronous generator is analyzed . withmcs - 196 series single chip micro - controller of high price performance ratio , a high precision , intelligent instrument for automated testing has been developed 设计了同步发电机参数测试仪器，完成了利用发电机定子电压电流的波形，辨识发电机参数的计算机软件，该装置运用锁相环技术自动跟踪和获取电量频率，进行交流采样，利用傅立叶算法求得电量基波的幅值、有效值，从而可获得三相有功功率、三相无功功率以及功率因数。
In the simulation experiment , the whole system model is founded by the software matlab / simulink . using the stator active power computed from the maximal output power of the wind turbine as the reference value of vector control system , the result of experiment approves that the control strategy is true . not only the frequency of stator current is constant , but the control of stator active and reactive are decoupled , and the output power tracks the maximal power of wind turbine 在最后的仿真实验中，本文利用matlab软件建立了系统各部分的仿真模型，选用与风力机最大输出功率对应的定子有功功率作为矢量控制的参考值做了仿真实验，并给出了仿真结果，验证了定子磁链定向矢量控制策略的正确性：既保证了定子输出频率的恒定，又达到了有功功率无功功率独立解耦控制的目的，同时还较好地跟踪了风力机的最大功率输出。
A new full - wave measurement circuit structure is put forward that would increase distribution automation system reliability and veracity . the distributed protection and monitoring unit in this paper can instead of general instruments of low voltage distribution system . it not only combines ampere meter , voltage meter , active power meter , reactive power meter and power meter , frequency meter into a meter , but also increases monitoring position switch , control bus switching alternately and monitoring energy 本文研制的保护和测控单元，可替代低压配电系统中所使用的常规仪表，将原来回路需要的电流表、电压表、有功功率表、无功功率表和功率因数表、频率表简化为一块表，并增加了位置开关量检测，控制母线投切和电度监测功能，从而极大的简化了低压配电二次仪表设计、安装调试，提高了运行、维护和管理水平。
How the parallel inverters share the output power is analyzed and a completely different conclusion is got that the output active power ' s difference and passive power ' s difference of two parallel inverters are relative to both the output voltage amplitude ' s difference and output voltage phase ' s difference of the two parallel inverters 接着对并联逆变器的功率均分进行了建模分析、仿真分析和实验验证，得出一个同以往不同的结论：两台逆变器输出的有功功率差和无功功率差与输出电压的相位差和幅值差都有关系。
